Abstract: A fault indicator for indicating the occurrence of a fault in an electrical conductor has a housing, a high capacity battery, a plurality of emitting diodes (LEDs) visible from the exterior of the fault indicator upon the occurrence of a fault, and electronic circuitry for sensing a fault, for actuating the LEDs to indicate a fault and to provide a timed reset of the LEDs to a non-fault indicating condition a predetermined time after the fault has occurred. The electronic circuitry, including a microprocessor that is normally in a sleep mode, conserves energy by drawing insubstantial current from a high capacity battery during non-fault conditions. Preferably, the microprocessor controls activation of the fault indicating LEDs with pulse width modulated (PWM) signals during defined time intervals for improved visibility. Visibility is further improved where the PWM signals for the indicator LEDs are interleaved in time to provide a highly distinctive flicker effect.
Type:
Grant
Filed:
October 25, 2002
Date of Patent:
May 30, 2006
Assignee:
E.O. Schweitzer Mfg. Co.
Inventors:
Kurt James Fenske, Laurence Virgil Feight
Abstract: A fault indicator for detecting the occurrence of a fault current in a monitored conductor and providing a light indication thereof includes a rotatably mounted indicator flag. The flag is positioned in either a reset indicating or a fault indicating state by a magnetic pole piece, which is magnetized in one magnetic direction or the other by momentary application of a current in one direction or the other to an actuator winding on the pole piece. A magnetically actuated reed switch in an auxiliary magnetic circuit comprising an auxiliary pole piece magnetized by the actuator winding and a bias magnet magnetically aligned to oppose the reset magnetic orientation and reenforce the trip magnetic orientation of the magnetic pole piece closes upon occurrence of the fault current to connect an internal lithium battery to an LED visible from the exterior of the fault indicator housing.
Type:
Grant
Filed:
March 30, 1999
Date of Patent:
August 13, 2002
Assignee:
E.O. Schweitzer Mfg. Co.
Inventors:
Edmund O. Schweitzer, Jr., Kirk S. Thomas